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/*
* Copyright (C) 2005-2016 Junjiro R. Okajima
*/
/*
* file private data
*/
#include "aufs.h"
void au_hfput(struct au_hfile *hf, struct file *file)
{
/* todo: direct access f_flags */
if (vfsub_file_flags(file) & __FMODE_EXEC)
allow_write_access(hf->hf_file);
fput(hf->hf_file);
hf->hf_file = NULL;
atomic_dec(&hf->hf_br->br_count);
hf->hf_br = NULL;
}
void au_set_h_fptr(struct file *file, aufs_bindex_t bindex, struct file *val)
{
struct au_finfo *finfo = au_fi(file);
struct au_hfile *hf;
struct au_fidir *fidir;
fidir = finfo->fi_hdir;
if (!fidir) {
AuDebugOn(finfo->fi_btop != bindex);
hf = &finfo->fi_htop;
} else
hf = fidir->fd_hfile + bindex;
if (hf && hf->hf_file)
au_hfput(hf, file);
if (val) {
FiMustWriteLock(file);
AuDebugOn(IS_ERR_OR_NULL(file->f_path.dentry));
hf->hf_file = val;
hf->hf_br = au_sbr(file->f_path.dentry->d_sb, bindex);
}
}
void au_update_figen(struct file *file)
{
atomic_set(&au_fi(file)->fi_generation, au_digen(file->f_path.dentry));
/* smp_mb(); */ /* atomic_set */
}
/* ---------------------------------------------------------------------- */
struct au_fidir *au_fidir_alloc(struct super_block *sb)
{
struct au_fidir *fidir;
int nbr;
nbr = au_sbend(sb) + 1;
if (nbr < 2)
nbr = 2; /* initial allocate for 2 branches */
fidir = kzalloc(au_fidir_sz(nbr), GFP_NOFS);
if (fidir) {
fidir->fd_bbot = -1;
fidir->fd_nent = nbr;
}
return fidir;
}
int au_fidir_realloc(struct au_finfo *finfo, int nbr)
{
int err;
struct au_fidir *fidir, *p;
AuRwMustWriteLock(&finfo->fi_rwsem);
fidir = finfo->fi_hdir;
AuDebugOn(!fidir);
err = -ENOMEM;
p = au_kzrealloc(fidir, au_fidir_sz(fidir->fd_nent), au_fidir_sz(nbr),
GFP_NOFS);
if (p) {
p->fd_nent = nbr;
finfo->fi_hdir = p;
err = 0;
}
return err;
}
/* ---------------------------------------------------------------------- */
void au_finfo_fin(struct file *file)
{
struct au_finfo *finfo;
au_nfiles_dec(file->f_path.dentry->d_sb);
finfo = au_fi(file);
AuDebugOn(finfo->fi_hdir);
AuRwDestroy(&finfo->fi_rwsem);
au_cache_free_finfo(finfo);
}
void au_fi_init_once(void *_finfo)
{
struct au_finfo *finfo = _finfo;
static struct lock_class_key aufs_fi;
au_rw_init(&finfo->fi_rwsem);
au_rw_class(&finfo->fi_rwsem, &aufs_fi);
}
int au_finfo_init(struct file *file, struct au_fidir *fidir)
{
int err;
struct au_finfo *finfo;
struct dentry *dentry;
err = -ENOMEM;
dentry = file->f_path.dentry;
finfo = au_cache_alloc_finfo();
if (unlikely(!finfo))
goto out;
err = 0;
au_nfiles_inc(dentry->d_sb);
/* verbose coding for lock class name */
if (!fidir)
au_rw_class(&finfo->fi_rwsem, au_lc_key + AuLcNonDir_FIINFO);
else
au_rw_class(&finfo->fi_rwsem, au_lc_key + AuLcDir_FIINFO);
au_rw_write_lock(&finfo->fi_rwsem);
finfo->fi_btop = -1;
finfo->fi_hdir = fidir;
atomic_set(&finfo->fi_generation, au_digen(dentry));
/* smp_mb(); */ /* atomic_set */
file->private_data = finfo;
out:
return err;
}
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